Sukhoi Superjet commander Denis Evdokimov, who flew Aeroflot flight SU 1492, was sentenced on June 20 to 6 years in prison. The plane burned down during an emergency landing at Sheremetyevo as a result of a plane crash on May 5, 2019. As a result of this disaster, 41 people burned down, only the pilot Evdokimov was found guilty. However, according to the expert, everyone should have been responsible for the disaster – from the aircraft manufacturer to the airline and dispatchers, since the main causes of death of people are the materials from which the aircraft's inner skin was made, the chassis design that pierced the fuel tanks, as well as simulators not intended for the normal training of pilots in such an emergency. At the same time, the investigation itself was closed after only six months. Typically, such investigations take years.
Like most aviation accidents and disasters, the SSJ-100 Superjet crash at Sheremetyevo is a combination of certain factors.
“The verdict that we see is absolutely vile, where once again all the blame for the plane crash is shifted to the pilot Denis Evdokimov. The only difference is that in this situation the pilot survived and received a sentence, ”the Russian aviation expert told The Insider on condition of anonymity.
Lightning and simulators without working out "goat"
“Of course, the pilot is at fault, because he violated several rules for landing an aircraft with a maximum take-off weight, but the fault is not only with the pilot. How did the events take place? An airplane flies, lightning strikes it, all onboard systems fail, and the pilot decides to turn around and return to the airport of departure and make an emergency landing. Of course, each aircraft during the tests is tested by static electricity. Here, as the investigators assure, the lightning force was so great that all the equipment failed and it was not possible to simulate electricity of such power as the lightning struck the plane on any stand.
Okay, let's assume that it is. During the landing approach, the pilot made several mistakes, made a goat (jumped along the runway) and at some point the vertical component of the speed became so large that he flopped onto the runway. Pilots should be trained to land without running out of fuel."
Evdokimova's lawyer Natalya Mintusova also spoke about the fact that there was no such training. According to her, the SSJ flight simulator software did not even contain elements for working out such situations.
“During the investigation, it was confirmed that the simulator software in Direct Mode on the simulator at Aeroflot did not contain an element for working out actions in the event of a “goat” – separation from the runway when the pilot landed once, then again,” she said. Mitusov. – Pilots were not taught how to act in such a situation. The SuperJet simulator software did not allow to work out separation from the runway.
The simulator contains software that simulates various situations. The developer must test the aircraft. Work out the system with a test pilot. Then they write recommendations on how to act, one might say, a recipe. In our case, how to act as a pilot in case of a “goat”. Put it in the training program. With the help of this program, the pilot instructor on the simulator teaches the pilot the correct actions. If this element does not work out for him, they work out until he does not succeed. It didn't happen."
Information about the absence of such an element was confirmed by the Sheremetyevo trade union of flight personnel (SHPLS).
“They were on other simulators, but not on this one. At the same time, the SuperJet is fundamentally different from other aircraft. Previous experience will not help,” says Igor Deldyuzhov, president of ShPLS. – There is a video of the plane landing. Due to the fact that the aircraft was flown in Direct Mode, spoilers did not come out – shields on the wing surface. In normal mode, they exit automatically. Here they must be released manually. The commander has two hands: with his left he controlled the joystick (it is also the side control stick), with the right he controlled the engine levers. And still need to put forward spoilers. This is a feature of the SuperJet. In any case, it had to be worked out. If not in reality, then on simulators.
But further to the actions of the pilot, the questions end and questions begin to the aircraft manufacturer, says the source of The Insider.
The third case when fuel tanks are pierced on the SSJ chassis
One of the claims that Evdokimov made was that he did not use up fuel, that is, excess weight, due to which the landing gear of a heavy aircraft pierced the fuel tanks upon landing. However, this aircraft did not have fuel drain systems, the expert of The Insider says, and it was impossible to fly and develop it due to the gradual shutdown of systems and high risks.
“The plane is landing, it has no opportunity to drain fuel, it can only fly and produce it, because emergency fuel drain systems are not installed on short-haul aircraft, only on wide-body and long-haul aircraft, because they have restrictions on maximum landing weight. Here, due to the failure of all systems, the continuation of the flight could lead to more serious consequences, so the pilot made the right decision to land without running out of fuel.
This was confirmed in the analysis of the "Sheremetyevo trade union of flight personnel" and aviation analyst Vladimir Karnozov.
“The situation developed abnormally, the pilot reasonably decided to land with a full tank. When you have a chain of failures, and you do not know what will fail next, it is logical to land the car as quickly as possible while it is at least somehow controlled.
That is why there are serious questions to the Irkut corporation, which once made SSJ civil aircraft, and now it is doing this as part of the United Aircraft Corporation. Why, with a strong vertical impact on the ground, the landing gear of the aircraft did not fold, as it should, but pierced the fuel tank?
“Because this aircraft has an incorrectly designed landing gear,” says the source of The Insider. – First of all, it is double-sided. Double-strut main landing gear are not fitted to regional, local, medium and short haul aircraft. They are placed only on wide-body long-haul vehicles. Neither Bombardier, nor Embraer, nor Boeing, nor Airbus put a two-strut landing gear on regional, medium- and short-haul aircraft.
Superjet landing gear incorrect. A similar case was once with a Superjet at the Yakutsk airport. When the runway was being repaired and the asphalt pavement was removed from part of the runway, the height difference was 30 cm, and when the plane, even at a relatively low speed, made a run along the runway, even there the landing gear pierced the fuel tanks and there was a jet fuel leak. Due to the fact that the speed was small, a spark did not form and all this did not catch fire. Even then, a similar case revealed problems with the landing gear. Even in such a case, as a height difference of 30 cm, it breaks through your fuel tank. The landing gear needs to be redone on this aircraft, it is wrong, wrongly positioned and wrongly designed. This was not done. Whatever the vertical component of the speed, the landing gear must not pierce the fuel tanks. They should fold to the sides. This is a question for the manufacturer.
There was a similar incident with the SSJ chassis also at the Zhukovsky airport in July 2018. Alexander Ivanov, a first-class test pilot, colonel, was awarded the “Order of Courage” for testing carrier-based aircraft in the critical conditions of the Arctic, spoke about him. For a long time he worked as the lead tester of the flight service of JSC Sukhoi Civil Aircraft, and he played a key role in SuperJet tests, carefully recording all the design flaws of the aircraft. According to him, Sukhoi allegedly tried to convince him not to fix serious problems in the list of shortcomings after each test flight. After the disaster at Sheremetyevo, he was involved in the investigation, but when he became actively involved in it and said that it was probably not the pilot, but the technology, he was no longer involved in the investigation.
Then Ivanov went to Evdokimov's lawyers and presented his arguments to them. In particular, he said that in the summer of 2018 there was also a situation with the landing of the SSJ, during which the landing gear again deformed the tank. “Insufficient rigidity of this section of the fuel tank wall has been known since the aircraft crash with the separation of the same right pillar in Zhukovsky,” the tester is convinced.
The design of the aircraft, or rather, the position of the landing gear under the fuel tanks, has not been corrected so far.
At the same time, Ivanov calls the SuperJet "simply an excellent aircraft" in normal operation, but recalls the need to "eliminate certain unacceptable inconsistencies", and primarily in the chassis. After trying to convince the Sukhoi leadership of this, Ivanov, according to him, even applied to the Prosecutor General's Office.
Mintusova also spoke about problems with the chassis.
“The landing gear is designed in such a way that it is attached through the power element of the wing part to the wall of the fuel tank. This is structurally unacceptable. Part 25 of the Aviation Regulations states that the destruction of the landing gear under no circumstances should lead to a fuel leak and, accordingly, to a fire.
That is, in fact, even with a very hard landing, the landing gear should fold, “bounce”, but not destroy the fuel system. If destruction does occur, then the reason must not be in the chassis, experts explain. The design of the aircraft, or rather, the position of the landing gear under the fuel tanks, has not been corrected so far.
Salon was not supposed to burn, melt and smoke
As a result of the disaster, most of the passengers died not from fire and burns, but from asphyxiation with carbon monoxide. According to the norms, the materials used in the cabin of the aircraft should not burn and should not melt with the release of smoke from the combustion of the inner skin, the anonymous expert explained.
“It is clear that everything else that is not inside the aircraft — communications, outer skin, components and assemblies — can burn and melt, but nothing inside the aircraft should melt and burn with the release of carbon monoxide and smoke. In this case, the passengers were poisoned precisely by the combustion products of the materials that were used in the manufacture of the aircraft cabin. How was this plane certified that there were materials from which the passenger cabin is made, which burn and melt with the release of carbon monoxide? It shouldn't be there. Again, this is a question for the manufacturer.
The fire trucks weren't ready
“The next question is for the Sheremetyevo airport dispatchers. Your plane flies with full tanks of fuel, with failed electronics and avionics. Even assuming that in this case you rely on the pilot and that he will land the plane without any problems, then why weren't fire engines and ambulances sent to the runway just in case? It is clear that the landing gear was released from the aircraft. It is clear that they are in the landing position. Why did the Sheremetyevo airport dispatcher not call these cars? I can understand that no instructions were given to process the strip so that there would be no spark, one could rely on the pilot. But why was it impossible to play it safe and send firefighters and ambulances to the runway? These are questions to which there is no answer. The airport is not to blame for anything, nor is the company that maintained the aircraft, nor is the airline whose pilot banged the plane on the runway, nor is the aircraft manufacturer to blame. No one is to blame, only the pilot was blamed. I do not relieve him of responsibility, gross mistakes were made during the landing, but still everyone blamed everything on one, and the problem is complex, requiring a normal investigation and solution in order to prevent such disasters. And from this point of view, the verdict is simply disgusting.”